Learn how to trace a bad screencapture of Anime-series...

This tutorial will teach you how to change the colour of a car, no adding flames or rims just changing the colour for now.

Learn how to change the color of eyes.

This tutorial with guide you through how to change the colour of a car.

Well, the answer actually depends on the value (lightness/darkness) of the red and green used, when you're dealing with Multiply Mode in Photoshop.

You may have caught on by now that Photoshop has "opposite" blend modes: Darken vs. Lighten, Multiply vs. Screen, and Color or Linear Burn vs. Color or Linear Dodge. So the definition in Photoshop Help for Color Dodge may sound eerily familiar:

Provides an excellent fade into grayscale.

Ever wanted to color those boring black and white anime?

Start by opening a image.
Press Ctrl+U to open hue/saturation window. Apply settingsa as shown.
Duplicate the layer.
From layer pallete change the color mode to linear dodge.

Photoshop has what it calls "Blending Modes." In the Layers palette, these options show up in the drop-down that is usually set to "Normal." You can also set the blending mode (and access more options) by going to the Layer Style dialog box.